Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/22—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising organic material
  • B01J20/26—Synthetic macromolecular compounds
  • B01J20/261—Synthetic macromolecular compounds obtained by reactions only involving carbon to carbon unsaturated bonds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/22—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising organic material
  • B01J20/26—Synthetic macromolecular compounds
  • B01J20/265—Synthetic macromolecular compounds modified or post-treated polymers
  • B01J20/267—Cross-linked polymers
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
  • C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
  • C07D307/34—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
  • C07D307/38—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with substituted hydrocarbon radicals attached to ring carbon atoms
  • C07D307/40—Radicals substituted by oxygen atoms
  • C07D307/46—Doubly bound oxygen atoms, or two oxygen atoms singly bound to the same carbon atom
  • C07D307/48—Furfural
  • C07D307/50—Preparation from natural products

Definitions

• the invention concerns the method of separation of furfural from diluted aqueous solutions.
• Furfural is manufactured by acid hydrolysis of plant residues. This process produces diluted aqueous solutions in which furfural is contained in concentration as low as 1%. Common methods of furfural separation from these solutions are distillation and extraction by suitable solvents. (Encyklopedia of Chemical Procesing and Design, Marcel Dekker Inc., vol. 24, p. 53, New York 1986) Both methods have serious disadvantages. Distillation of aqueous furfural solutions is complicated by the formation of the azeotrope which at the atmospheric pressure contains approx. 36% of furfural. After condensation the azeotrope separates into two layers, the aqueous one is recirculated and from the remaining one liquid pure furfural is obtained in the second distillation step.
• the first distillation step is possible to replace by extraction using a suitable solvent immiscible with water. In this case, the complications are caused by traces of the extracting solvent in waste waters.
• the present invention relates to the process in which furfural is separated from its aqueous solutions using a bed of chemically inert polymer adsorbent.
• the polymer adsorbent is a porous copolymer of styrene and its derivatives with surface area higher than 30 m 2 /g from which furfural is subsequently desorbed by an alcohol with 1-3 carbon atoms.
• the polymer acts as a heterogenized extraction agent whose affinity toward furfural molecules is much higher than the affinity of water molecules.
• the bed of polymer adsorbent saturated by furfural is possible to regenerate by a solvent in which furfural is substantially better soluble than in water but which has small affinity toward the polymer, that is, a solvent in which the polymer does not swell.
• a solvent in which the polymer does not swell for this purpose alcohols with 1-3 carbon atoms are suitable.
• furfural was contained in concentration at least ten times higher than had been its concentration in original aqueous solution.
• the separation of furfural from alcoholic solution by adsorption separation is not complicated by the azeotrope formation and due to the low heat of vaporization of the alcohol, it is less energy-demanding than the distillation of aqueous solutions.
• the solvent used for the adsorbent regeneration can be recirculated.
• the adsorptive separation according to present invention is substantially more energy-efficient. This new process is also able to separate furfural from very diluted solutions containing less than 1% of furfural for which traditional methods using distillation or extraction are quite unsuitable.
• an adsorbent having the BET surface area 750 m 2 /g was prepared by the method of crosslinking in swollen state described in DDR Pat. No. DD 249,274.
• first traces of furfural in the eluate were observed after passing of 210 cm of 1% aqueous furfural solution through the column.
• furfural was desorbed from the column in 33 cm 3 of n-propanol.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Analytical Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Solid-Sorbent Or Filter-Aiding Compositions (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=5434171

Family Applications (1)

Country Status (6)

Cited By (1)

Families Citing this family (1)

Citations (2)

• 1988
  • 1988-12-16 CS CS888371A patent/CS271942B1/cs unknown
• 1989
  • 1989-12-15 US US07/452,269 patent/US5011611A/en not_active Expired - Fee Related
  • 1989-12-15 DE DE3941528A patent/DE3941528A1/de not_active Withdrawn
  • 1989-12-15 FI FI896023A patent/FI896023A7/fi not_active IP Right Cessation
  • 1989-12-15 CA CA002005632A patent/CA2005632A1/en not_active Abandoned
  • 1989-12-15 SE SE8904232A patent/SE8904232L/xx not_active Application Discontinuation

Patent Citations (2)

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